How can we move forward with the fluoridation debate? Hamilton City Council has an obligation to show that its decision will not cause harm

Fluoridation of public water supplies is a public health measure that has been around since the 1940s. Its benefit in reducing tooth decay in children and to a lesser extent in adults has long been established. Why then is it still being contested so fiercely in New Zealand and why did Hamilton City decide to stop it?

There seem to be three main reasons that might be headed roughly: ‘don’t mess with our water’; ‘fluoride is poisonous’ and ‘we don’t need it’.

Don’t mess with our water. There is an objection to any intervention of this kind. It has elements of reason, emotion and politics. On the reason side is the knowledge that any attempt at improving on nature no matter how desirable its intention can have unforeseen consequences that are less desirable. The emotional element is the fear of alteration of what we eat and drink by forces that are outside our control and our understanding. The political element is the over-arching belief that individuals, not government, should take care of their health needs.

Fluoride is poisonous. There is the concern that fluoride may have toxic effects. A subset of this concern is the knowledge that there is a quantity of fluoride much larger than can be ingested from normally fluoridated water that is undoubtedly toxic and there is always the possibility, no matter how small, that such a quantity might accidentally be added to the water supply.[1]

Over the years, as researchers have investigated the properties of fluoride there have been papers published in reputable scientific journals raising questions as to whether fluoride ingestion in quantities obtainable from a fluoridated water supply is related to an increased risk of osteosarcoma, reduced IQ, skeletal fluorosis, dental fluorosis and no doubt other conditions.

We don’t need it. The third objection is that in modern times, since fluoride has been included in dental products such as toothpastes and mouthwashes, there is no longer a need for it to be added to the water. Research has shown some of these products to be effective in preventing tooth decay

So why would you want to have fluoride in your water?

The ‘don’t mess with our water’ objections should be examined in the context of other public health measures. A broad definition of public health measures would include public access to the basic requirements for health; adequate nutrition, care, sanitation, exercise, shelter and clothing but let’s confine ourselves to interventions by authorities that deal with a specific issue. So, usually included would be: removal of lead from paint and petrol, iodisation of salt, and immunisation against poliomyelitis, meningococcal disease, measles and other infectious diseases.

Provision of clean, potable water is a public health measure with historic significance. It was John Snow, a London physician and the father of epidemiology, who found that public water supplies were the source of the cholera epidemic in Soho in 1854. An apocryphal story has him removing the handles from the pumps on the contaminated wells, an early public health intervention. In any event the epidemic was brought to an end and an understanding gained of the importance of the quality of drinking water to health. The provision of a healthy water supply is now an elaborate process that is applied in cities and towns worldwide, usually under the direction of local authorities. Additives are required to deal with particulate, viral, bacterial and chemical contamination.

In the early days of fluoridation it had been found that some water supplies had natural fluoride in amounts that prevented tooth decay. Others did not and it was argued that authorities in these cities and towns had a responsibility to correct the deficiency.

To the argument that fluoride is toxic in amounts that are ingested from fluoridated water supplies it can be said that no reputable research has so far been able to demonstrate that this is the case. Research that has raised the possibility of significant fluoride-produced toxic side effects, has so far been answered. An example is a possible association with increased risk of fractures.[2] The most recent is a Chinese study suggesting a lowering of IQ in populations drinking fluoridated water. It seems to be on the way to being resolved.[3],[4]

The argument that we no longer need fluoride in water because it’s in toothpaste and mouthwash clearly has validity although there are certain to be some children who will miss out because they don’t use these products. The question of how significant the difference is in a modern setting has been answered by at least one before-and-after study in an area that stopped fluoridation of its water supply. They found that the incidence of dental caries in ten-year-olds increased following cessation of fluoridation.[5]

My plea to the Hamilton City Council is to commit to an independent research project that compares rates of tooth decay before and after cessation of fluoridation. It’s the least they can do to meet their obligation to Hamilton’s children. The project should also include comparison of rates of any feared side-effect of fluoride ingestion, such as osteosarcoma. Such a study would provide valuable information on which the New Zealand public and local authorities might base decisions on what should be in their drinking water.

[1] Gessner, B., Beller, M. (1994) Acute fluoride poisoning from a public water system. The New England Journal of Medicine, 330, 95-99.

Comments (24)

Wasting your time sir. These people are immune to reason, scientific facts and have no commitment to the democratic process given their overeturning of the binding referendum result. One can only hope that someone challenges this latter point in court.

You talk about meningococcal disease. The introduction of the MeNZB vaccine was a huge expense and was unnecessary. It was a misuse of taxpayers' money. The Ministry of Health said that dozens of lives would be saved but, in the end, officials and expects admitted that "an estimated 1.7 deaths were prevented". As was predicted by those who questioned the roll-out of the vaccine: "If it works, the MeNZB vaccine will prevent at most 1-2 deaths per year out of 700 deaths in under 20 year olds." Few (if any) journalists looked at the roll-out in any depth.

We need to be more critical when analysing policies and their potential effects. In the case of fluoridation, shouldn't fully informed adults decide what they want to drink?

1. I included the New Zealand immunisation campaign against Group B meningococcal disease (2004-2006) in my examples of public health measures, not because it was easy to demonstrate that its outcome was successful but because it was a New Zealand initiative that, at the time it was begun represented, in my view, a commendable effort to bring to an end an epidemic (1991-2006) that by 2004 had resulted in 5,000 hospitalisations and 200 deaths. In hindsight it appears that the epidemic was in decline at the time the campaign began, but who could be sure then or, for that matter, even now. It very likely had the benefit of reducing the disproportionate burden of Group B meningococcal disease in the population of disdavantaged New Zealand children.

2. John Colquhoun was a Principal Dental Officer in Auckland and in his latter years a well known opponent of fluoridation. The scientific basis for his views has been well refuted, for example by Newbrun and Horowitz.

As Ian Hassall says, the meningococcal epidemic may well have been on the wane by the time immunisation was begun, but that could only have been spotted in the rear vision mirror, so to speak. Moreover, as was pointed out often at the time - but the point was mostly missed by journalists - it wasn't just about deaths, it was about the number of cases. And immunisation made a huge difference to the number of cases. Don't forget the terrible damage meningococcal disease can do to the body, yet the patient survives. Just on those grounds, immunisation more than paid for itself.

But back to fluoride. I worked for John Colquhoun. He was a great person to work for, with a very liberal approach to his job in all its complexity. But he was wrong about fluoride: see Ian Hassall's note above. It wasn't until near the end of his career that his views on fluoride changed and he became an opponent.

the meningococcal epidemic may well have been on the wane by the time immunisation was begun, but that could only have been spotted in the rear vision mirror, so to speak

Peggy, that isn't correct. There were sceptics who pointed out at the time of roll-out that the "epidemic" - and you use the word loosely because there really was no epidemic - was in decline. As noted in one of my links above, Norway declined to roll out the same vaccine because of concerns about its efficacy and because the disease was on the wane.

You provide no support for your comment that "immunisation more than paid for itself." Tresury refused to support the introduction of the vaccine on the basis that it didn't stack up on a cost-benefit basis.

I worked for John Colquhoun. He was a great person to work for, with a very liberal approach to his job in all its complexity. But he was wrong about fluoride:

In other words, you disagreed with him on fluroide so he must have been wrong! His views are supported by many others, especially his view that in unfluoridated areas, the rate of tooth decay has fallen significantly. In 1997, the Lord Mayor's Taskforce in Queensland rejected the introduction of fluoride. It cited Dr Colquhoun, among others. It's report is well worth reading.

'Not an epidemic' !. What are you trying to say? You can call it an epidemic or call it Henry, but 200 deaths and 5,000 hospital admissions from a disease that had previously been relatively quiescent, in a pattern that other countries had suffered and potentially vaccine-preventable. What would you have done?

'Not an epidemic' !. What are you trying to say? You can call it an epidemic or call it Henry, but 200 deaths and 5,000 hospital admissions from a disease that had previously been relatively quiescent, in a pattern that other countries had suffered and potentially vaccine-preventable. What would you have done?

Ian,

The 200 odd deaths occurred over many years (between 1991 and roll-out) although I am aware that one editorial writer claimed that the deaths had occured in a single year. Significantly, the Ministry of Health kindly included figures for ALL strains of the disease in its promotional material and public statements. Why would it do such a dishonest thing when the MeNZB vaccine applied to one strain only? Presumably, the MOH didn't think the "epidemic" was of sufficient size which is why it added figures for other strains to bolster its message and scare parents into vaccinating their kids.

I would have been honest with parents telling them the disease was on the wane. I wouldn't have exaggerated the problem. What are the risk factors? These should have been communicated effectively to parents. I would also have ensured that the huge sum of money spent on the vaccine was examined critically from a cost-benefit perspective. It is clear that taxpayers didn't get value for money. I note that a relatively small number of children are affected by the disease which continues to kill (6 died last year).

I’m new to blogging and its (unwritten?) rules. At this point do I say nothing and assume readers will see what kind of person Ross has revealed himself to be? Or do I gently chide him, saying ‘That’s a trifle callous Ross’ and run the risk of ‘gotcha’ politics which Mr Shearer in his early days as leader said we mustn’t do, not to mention the possibility of provoking a tedious shouting match. Or are we bloggers driven by the need to always say something rather than nothing? Advice please.

With regard to John Colquhoun: I didn't say that he was wrong because I disagreed with him. I pointed to the rebuttal link posted by Ian Hassall in the comment immediately preceding mine. And I didn't say that I disagreed with him, either; we had considerable respect for his credibility on matters dental, and when he first began to change his views on fluoride, we listened. But later, I read the literature, and realised that he was wrong. It's unfortunate that people are still relying on his views in the matter of water fluoridation. Go look at the SCHER report, recently produced for the European Commission. I posted a link to it elsewhere on this blogsite: Tim Watkin's blog on the same topic.

Meningococcal disease: I reiterate, it wasn't just about the deaths, tragic as they were. It was at least as much about the cases, and the terrible damage that meningococcal disease can cause, yet the patient survives. As I said earlier, it is on that score alone that the vaccine more than paid for itself. And it surely looked like an epidemic to those of us with children in the age group most at risk; the sheer capriciousness of it, and the suddenness of deaths from it, scared the hell out of us. If it looks like a duck and all that..... an epidemic isn't measured by deaths alone.

I was very young when the Salk polio vaccine became available here in New Zealand. We were experiencing another polio outbreak (1955-56), not as severe as previous epidemics, but quite bad enough to scare the daylights out of parents of young children. Again, it may well have been on the wane. But when New Zealanders were offered a vaccination against it, parents fell on it with relief, and we children were lined up and jabbed, without any say in the matter. There were so many children in the schools of my youth with the withered limbs or the leg calipers that were the markers of a bout of polio. And they were the lucky ones: alive and well enough to go back to school. That vaccination campaign staved off further outbreaks of polio; in the early 1960s, the Sabin vaccine came along and, as the saying goes, the rest is history.

Pretty much nobody born after about 1960 has the least idea what a world with the ever-present threat of polio was like. Yet I wonder if, in today's environment, it would even be possible to get a polio vaccination campaign off the ground.

@ Ian - you're doing well. But don't be upset at Ross, he's working under different rules. This is not a question of integrity, but of the reliability of data and projections.

The old epidemics, Spanish 'flu etc., were simple matters where a clear public mandate was easy to find. As risks diminish or complications arise the matter becomes increasingly murky. On a strict science basis, something like smoking could readily be banned, but those who enjoy it would not necessarily welcome the restriction of their freedom.

The problem with fluoride is accumulating and presenting data that satisfies the public concerns of long term low dosage toxicity. No-one gets to play gotcha - it's as if your skeptical junior colleague required more data. Nothing unhealthy about that.

I’m new to blogging and its (unwritten?) rules. At this point do I say nothing and assume readers will see what kind of person Ross has revealed himself to be? Or do I gently chide him, saying ‘That’s a trifle callous Ross’ and run the risk of ‘gotcha’ politics which Mr Shearer in his early days as leader said we mustn’t do, not to mention the possibility of provoking a tedious shouting match.

Ian,

You can say whatever you like!

I personally think it's callous to focus on 1 or 2 deaths (of under 20 year olds) and ignore the hundreds of deaths in the same age group. Why do those one or two get special treatment? As Burnstyn and Law noted in their article to which I linked,

Based on 2003 and 2004 figures, if the vaccine proves effective then it could avert one or two deaths per year out of a total of 700 deaths for the 0 to 20 age group per annum. ... Based on that cost-benefit, the government would be spending 100 billion in preventing the rest of the 700 from dying.

Would you agree that spending $100 billion on trying to prevent 700 deaths is unrealistic, especially considering NZ's entire health budget is about $14 billion?

We are getting a little off-topic but I think this debate helps to explain why there is opposition to water fluoridation. The public do not necessarily trust what they're told by officials, and with good reason.

Ross, there is a clear public interest in vaccinating against fatal contagious diseases, given that the vaccines are effective with limited negative effects. It could be argued that there is a kind of neglience in not vaccinating, as unvaccinated people serve as potential reservoir for the disease. This grossly oversimplifies issues like the possible role of the CHAT vaccine development in the evolution of AIDS, but lets not get into that.

Tooth decay is much murkier. I'm agnostic on the issue, neither believing assertions that fluoridation is safe, nor the wilder speculations of the anti-fluoride people, which I think are sometimes partly rooted in a kind of proto-libertarian mistrust of authority which is occasionally ill-founded.

Ross, there is a clear public interest in vaccinating against fatal contagious diseases, given that the vaccines are effective with limited negative effects

That depends on several factors. Some vaccines might be more (or less) effective than others. For some diseases, especially those affecting small numbers of the population, a vaccine might be unnecessary or a luxury. The health budget is limited and there are competing priorities. Importanly, though, the fact remains that vaccinating kids is not compulsory; but for some, drinking fluoridated water is compulsory.

Ian, sorry I've been slow to answer your question (though it worked rather well rhetorically anyway!). I thought you handled that rather well. I'd add that the Pundit-specific rule is 'play the ball and not the person'. Riguour good, insults bad.

Ross, in what way is drinking fluoridated water compulsory? I've lived in places where I bought all my drinking and cooking water from the supermarket, not because of safety concerns but simply because the tap water was so heavily mineralised it tasted like s*** and food cooked with it tasted like s***. It was just a very minor expense and minor inconvenience, and if I had any objections to the water here I would happily do the same now.

Ross, vaccination, or at least treatment is not entirely voluntary you know. There are a number of conditions for which failure to have them treated could restrict your freedom of movement. This is perfectly proper.

But for many people tooth decay is not as serious as this group. The flipside is that the evidence for damage from fluoridation is not conclusive. In the days NZ had a trusted and trustworthy paternalistic government the decision to fluoridate seemed sensible. Now that we have an untrusted and untrustworthy assemblage of ambulant dog-tucker instead of a government, it becomes increasingly difficult to form social consensus. In the circumstances, Hamilton choosing to have hearings, and now moving toward a referendum model is almost inevitable.

In the sense that if you drink from water supplied to your house! Yes, of course, we could all buy bottled water but then studies have shown that some bottled water is nothing more than tapwater. Think of the explosion in discarded waste if we all bought bottled water, not to mention the cost. That wouldn't be a realistic option for many people.

I think this is one of those debates that will never cease, but perhaps we should ask dentists what they think about water fluoridation, they are the experts in the domain. I'll make sure to find out Trillium Dental doctors opinion on the matter, I've heard so many pros and cons on the subject that my head is spinning.